Genetics: Clinical Scenario
Which of the following is true regarding an X-linked dominant disease? A. More females than males are affected. B. An affected male will produce affected sons. C. An affected male will not transmit the disease to his daughters. D. The disease may skip generations via carrier females. E. Carrier daughters of affected women will be unaffected.
A
The U.S. Department of Health and Human Services has designated Thanksgiving Day as National Family History Day. The Surgeon General encourages family members to discuss important family health information while sharing in holiday gatherings. This initiative is significant to nurses because: a. There are few genetic tests available to identify this information. b. Only physicians should obtain this detailed information. c. Clients cannot accurately complete these histories on their own. d. This is the single most cost effective source of genetic information.
A Incorrect: Although there are more than 1000 genetic tests available, the single most cost effective piece of genetic information is the family history. B Incorrect: Nurses are ideally suited to take the lead in ongoing efforts to recognize the significance of the family history as an important source of genetic information. C Incorrect: A newly developed computerized tool called My Family Health Portrait was made available free of charge (www.hhs.gov/familyhistory/download.html). Others tools to aid the lay community in completing their family histories have been made available to the public. D Correct: Although there are more than 1000 genetic tests available, the single most cost effective piece of genetic information is the family history.
A key finding from the Human Genome Project was: A. Approximately 20,000 to 25,000 genes make up the genome. B. All human beings are 80.99% identical at the DNA level. C. Human genes produce only one protein per gene; other mammals produce three proteins per gene. D. Single-gene testing will become a standardized test for all pregnant women in the future.
Approximately 20,500 genes make up the human genome, only twice as many as make up the genomes of roundworms and flies. Human beings are 99.9% identical at the DNA level. Most human genes produce at least three proteins. Single-gene testing (e.g., alpha-fetoprotein test) is already standardized for prenatal care. (A)
One of the most promising clinical applications of the Human Genome Project has been pharmacogenomic testing (the use of genetic information to guide a client's drug therapy). Which conditions are potential candidates for pharmacogenomic application? (Select all that apply.) a. Fragile X syndrome b. Deep vein thrombosis (DVT) c. Breast cancer d. Myocardial infarction e. Hemophilia
Associations between genetic variation and drug effect have been observed for a number of commonly used drugs. The conditions for which these are applicable include: DVT, breast cancer, and myocardial infarction. Gene therapy has been unsuccessfully used in hemophilia treatment. Fragile X syndrome is the leading cause of intellectual disability and lacks effective treatment of any kind. (B,C,D)
In presenting to obstetric nurses interested in genetics, the genetic nurse identifies the primary risk(s) associated with genetic testing as A. Anxiety and altered family relationships. B. Denial of insurance benefits. C. High false positives associated with genetic testing. D. Ethnic and socioeconomic disparity associated with genetic testing.
Decisions about genetic testing are shaped by socioeconomic status and the ability to pay for the testing. Some types of genetic testing are expensive and are not covered by insurance benefits. Anxiety and altered family relationships, high false positives, and ethnic and socioeconomic disparity are factors that may be difficulties associated with genetic testing, but they are not risks associated with testing. (B)
Which condition or treatment reduces the risk of morbidity in women with the inherited factor V Leiden disorder? A. Anticoagulant therapy B. Pregnancy C. Oral contraceptives D. Hormone replacement therapy
Factor V Leiden is the most common inherited risk factor for primary or recurrent venous thromboembolism. It is an autosomal recessive disorder that increases an individual's risk for blood clots in the legs and pulmonary emboli. This risk significantly increases if the woman is pregnant or is taking oral contraceptives or hormone replacement therapy. Prophylactic anticoagulation therapy decreases the risk of comorbidities. (A)
Which genetic testing tool helps detect protein abnormalities in the fetus? A. Linkage testing B. Molecular testing C. Cytogenetic testing D. Biochemical testing
Genetic analysis provides a complete picture of nucleic acids, chromosomes, and protein molecules associated with genetic disorders. Biochemical testing helps to identify protein abnormalities that may result in genetic disorders in the fetus. Linkage testing is helpful in identifying marker sequences that are complementary to the affected gene. Molecular testing is used for the analysis of nucleic acids. Cytogenetic testing helps in detecting abnormalities in chromosomes. (D)
A patient who has experienced frequent miscarriages is referred for chromosomal analysis. Which sample should the nurse obtain to conduct karyotyping for the patient? A. Urine B. Saliva C. Muscle D. Blood
Karyotyping is testing for the number, size, and forms of chromosomes; it is used to detect chromosomal abnormalities such as trisomy. Chromosomal abnormalities are the major causes of miscarriages, stillbirths, and other gynecological disorders. A blood sample is the preferred medium for determining chromosome abnormalities. Nucleated and replicating cells like white blood cells are extracted from the blood sample and chosen for karyotyping. Urine, saliva, and muscle samples are not used for analyzing chromosome number, because they do not undergo rapid division to form new cells. (D)
A woman has been diagnosed with factor V Leiden (FVL). The nurse caring for this woman would be alert for which of the following problems? A. Breast cancer B. Postpartum hemorrhage C. Deep vein thrombosis (DVT) D. Placenta previa
Key words: (factor V Leiden (FVL))(C)
During genetic testing of an infant, the health care provider finds that a very small piece of the long arm of chromosome 22 is missing. Which symptoms related to this finding will the health care provider and nurse explain to the child's parents? A. "Your child may have a mewing cry." B. "Your child may have short, broad hands." C. "Your child may have cardiac abnormalities." D. "Your child may have webbed fingers and toes."
Missing a small piece of the long arm of chromosome 22 indicates that the infant has velocardiofacial syndrome. It is a type of microdeletion that is characterized by cardiac and craniofacial abnormalities. Therefore, the nurse should inform the parents that the child will have cardiac abnormalities. Unlike Cri du chat syndrome, velocardiofacial syndrome is not characterized by a mewing cry. Unlike Down syndrome and hereditary syndactyly, velocardiofacial syndrome is not characterized by webbed toes and fingers. Unlike Down syndrome, velocardiofacial syndrome is not characterized by short, broad hands. (C)
The nurse finds that the patient has a family history of sickle cell anemia. The genetic reports of both the client and her partner revealed the presence of an autosomal recessive gene for sickle cell anemia. What is the possible chance of disease in their child? A. 5% B. 15% C. 20% D. 25%
Sickle cell anemia is an autosomal recessive inherited disorder. Because both partners have autosomal recessive genes, they are the carriers of sickle cell anemia. For the gene to express, each partner whould contribute a variant allele to the offspring. Therefore, the chance of expressing the gene in each child is 25%. (D)
A couple has been counseled for genetic anomalies. They ask you, "What is karyotyping?" Your best response is: A. "Karyotyping will reveal whether the baby's lungs are mature." B. "Karyotyping will reveal whether your baby will develop normally." C. "Karyotyping will provide information about the gender of the baby and the number and structure of the baby's chromosomes." D. "Karyotyping will detect any physical deformities the baby has."
The lecithin/sphingomyelin ratio, not karyotyping, reveals lung maturity. Although karyotyping can detect genetic anomalies, the range of normal is nondescriptive. Karyotyping provides genetic information, such as gender and chromosomal structure. Although karyotyping can detect genetic anomalies, not all such anomalies display obvious physical deformities. Deformities is a nondescriptive word. Furthermore, physical anomalies may be present that are not detected by genetic studies (e.g., cardiac malformations). (C)
The laboratory reports of a child revealed the presence of an extra 13th chromosome. Which condition is likely to be found in the child? A. Patau syndrome B. Down syndrome C. Turner syndrome D Edward syndrome
Trisomic conditions are categorized based on the number of the chromosome that is likely to be affected. Patau syndrome is also known as trisomy 13, in which the total count of chromosomes is 47. This is due to the presence of an extra 13th chromosome in such patients. Down syndrome is characterized by the presence of an extra 21st chromosome. Turner syndrome is seen in female patients with the absence of an X chromosome. Edward syndrome is characterized by the presence of an extra 18th chromosome. (A)
The nurse receives an order from the primary health care provider to collect a sample from a pregnant client for DNA karyotyping of the fetus. Which sample does the nurse collect? A. Nerve cells B. Muscle cells C. Red blood cells D. White blood cells
White blood cells are commonly used for DNA karyotyping, because they contain nuclei and divide rapidly. Nerve cells are nucleated but do not divide rapidly. Hence, they are not preferred for DNA karyotyping. Muscle cells are also nucleated, but they divide slowly. It will take a lot of time for DNA karyotyping, and the cells may die. Red blood cells do not contain nuclei; therefore, DNA karyotyping is not possible with red blood cells. (D)
The Human Genome Project, which began in 1990: a. Expects to complete a map of the entire human genome by 2010 b. Found that all human beings are 99.9% identical at the DNA level c. Has not yet been able to translate the accumulating raw research into anything medically practical d. Put its research relevant to nursing in a document published by the International Society of Nurses in Genetics (ISONG)
A Incorrect: The project completed its map ahead of schedule, in 2000. B Correct: The majority of the 0.1% genetic variations are found within and not among populations. C Incorrect: The project's research has been very valuable in the identification of genes involved in disease and in the development of genetic tests. D Incorrect: The ISONG document, the "Statement of the Scope and Standards of Genetics Clinical Nursing Practice," is very useful but not directly related to the Human Genome Project.
What best describes the pattern of genetic transmission known as autosomal recessive inheritance? A. Disorders in which the abnormal gene is carried on the X chromosome. B. Disorders in which the abnormal gene for the trait is expressed even when the other member of the pair is normal. C. Disorders in which both genes of a pair must be abnormal for the disorder to be expressed. D. Disorders in which a single gene controls the particular trait.
Autosomal dominant inheritance occurs when the abnormal gene for the trait is expressed, even when the other member of the pair is normal, such as in Huntington's disease or Marfan syndrome. An autosomal recessive inheritance disorder occurs when both genes of the pair are abnormal, such as in phenylketonuria or sickle cell anemia. Disorders in which a single gene controls the particular trait describe the unifactorial inheritance. X-linked recessive inheritance occurs when the abnormal gene is carried on the X chromosome, such as in hemophilia or Duchenne muscular dystrophy. (C)
***A 38-year-old maternity patient receives information based on genetic testing that her fetus has a deformity and decides to terminate the pregnancy. There is a family history of genetic abnormalities. Following the termination of pregnancy, the pathology report indicates that the fetus had no structural abnormalities. This finding suggests that: A. The patient should have asked for a second opinion from a perinatal specialist. B. The genetic test results provided indicated a false-negative finding. C. Genetic testing results vary with patient demographics and information provided. D. Results indicated a false-positive finding leading to an adverse outcome.
Because the pathology report identified no abnormalities, the results of genetic testing in this case were false-positive, in that they indicated that there was an abnormality when there was not. This information unfortunately led to a poor health outcome. Although no genetic test provides 100% reassurance, most patients do not automatically seek a second opinion unless there are additional variables that may influence the reliability of the result. Because the patient had a family history of genetic abnormalities, it is unlikely that the patient and/or provider would necessarily have opted for a second opinion. A false-negative result would indicate that a condition was not present even though it was; the patient was provided with a negative result. Genetic test results do not vary with patient demographics or information provided. (D)
Which statement regarding chromosomal abnormalities is most accurate? A. They occur in approximately 10% of newborns. B. Abnormalities of number are the leading cause of pregnancy loss. C. Down syndrome is a result of an abnormal chromosomal structure. D. Unbalanced translocation results in a mild abnormality that the child will outgrow.
Chromosomal abnormalities occur in less than 1% of newborns. Aneuploidy is an abnormality of number that also is the leading genetic cause of mental retardation. Down syndrome is the most common form of trisomal abnormality, an abnormality of chromosome number (47 chromosomes). Unbalanced translocation is an abnormality of chromosome structure that often has serious clinical effects. (B)
For which of these maternal diagnoses or incidents should prenatal testing be done? Select all that apply. A. Diabetes B. Hypotension C. Sickle cell disease D. Age over 25 E. Three or more miscarriages F. Chromosomal abnormality
The maternal diagnoses or incidents for which prenatal testing should be done include: diabetes; hypertension (not hypotension); sickle cell disease; age over 35 (not 25); three or more miscarriages; and chromosomal abnormalities. (A, C, E, F)
***A nurse is providing genetic counseling for an expectant couple who already have a child with trisomy 18. The nurse should do what? A. Tell the couple they need to have an abortion within 2 to 3 weeks B. Explain that the fetus has a 50% chance of having the disorder C. Discuss options with the couple, including amniocentesis to determine whether the fetus is affected D. Refer the couple to a psychologist for emotional support
Genetic testing, including amniocentesis, would need to be performed to determine whether the fetus is affected. The couple should be given information about the likelihood of having another baby with this disorder so that they can make an informed decision. A genetic counselor is the best source for determining genetic probability ratios. The couple eventually may need emotional support, but the status of the pregnancy must be determined first. (C)
Which activities are included in the role of a nurse practicing in the field of genetics? Choose all that apply. a. Assessing the responses of family members to a genetic disorder b. Performing genetic testing, such as amniocentesis c. Constructing a family pedigree of three or more generations d. Advising a pregnant mother whose fetus has a genetic disorder to have an abortion e. Offering parents information about genetics
(A,C,E) Correct: All of these are activities that a genetics nurse would carry out in caring for a family undergoing genetic counseling. Incorrect: Physicians perform amniocentesis; the nurse may assist in this procedure. It is important for nurses to be aware of their own values and beliefs and to refrain from attempting to influence the family. The nurse must respect the right of the individual or family to make autonomous decisions.
A woman is 5 months pregnant. On a routine ultrasound scan, the physician discovers that the fetus has a diaphragmatic hernia. The woman becomes distraught and asks the nurse what she should do. What action by the nurse is most appropriate? a. Talking to the woman and referring her to a genetic counselor b. Suggesting that the woman travel to a fetal treatment center for intrauterine surgery c. Telling her that everything is going to be fine d. Sitting with her and calmly suggesting that she consider terminating this pregnancy
A Correct: Before the woman makes any decisions, she should discuss this newly discovered information with a genetic counselor. Genetic counselors can help with the diagnosis and management of families affected by genetic conditions. B Incorrect: The discussion of potential surgery should be pursuant to genetic counseling. C Incorrect: This type of statement may give the woman false hope and is not accurate. D Incorrect: All options should be discussed with the genetic counselor. Furthermore, the guiding principle for genetic counseling is nondirectiveness. This respects the right of the individual or family being counseled to make autonomous decisions.
Which congenital malformations result from multifactorial inheritance (Select all that apply)? A. Pyloric stenosis B. Cri du chat syndrome C. Cleft lip D. Anencephaly E. Congentital heart disease
All these congenital malformations are associated with multifactorial inheritance, except cri du chat which is related to chromosome deletion. (A,C,D,E)
A client is 5 months pregnant. On a routine ultrasound scan, the physician discovers that the fetus has a diaphragmatic hernia. The woman becomes distraught and asks the nurse what she should do. Which response would be most suitable? A. Talk to the client, and refer her to a genetic counselor. B. Suggest that the client travel to a fetal treatment center for intrauterine surgery. C. Tell her that everything is going to be fine. D. Sit with the client, and calmly suggest that she consider terminating this pregnancy.
Before the client makes any decisions, she should discuss this newly discovered information with a genetic counselor. Genetic counselors can help with the diagnosis and management of families affected by genetic conditions. The discussion of potential surgery should be pursuant to genetic counseling. Telling the woman that everything is going to be fine may give her false hope and is not accurate. All options should be discussed with the genetic counselor. Furthermore, the guiding principle for genetic counseling is nondirection, which respects the right of the individual or family who are being counseled to make autonomous decisions. (A)
The provider has ordered a genetic testing to assess whether the patient's fetus is at risk for sickle cell disease. The patient is asymptomatic but relates a positive family history. On the basis of this information, the nurse realizes that the provider has ordered: A. Predictive testing. B. A carrier screening test C. Presymptomatic testing. D. Predispositional testing.
Carrier screening test would help identify whether the mother had the genetic mutation, thereby increasing the risk for transmission to the fetus. Predictive testing is used to determine genetic status of an asymptomatic family member. Presymptomatic testing would indicate the presence of a specific genetic mutation that is associated with a clinical presentation that would occur over the course of time. Because sickle cell disease is an autosomal recessive transmission and the patient is asymptomatic, such testing would not be indicated. Predispositional testing would also not be indicated because sickle cell disease is an autosomal recessive disease; if the patient is asymptomatic and a genetic mutation is found, it would exist only in a carrier state. (B)
On reviewing the genetic test report of a child, the nurse finds that the child has fragile X syndrome (FXS). Which behavioral symptoms does the nurse observe in the child? Select all that apply. A. Delusions B.Hyperactivity C. Hallucinations D. Poor eye contact E. Repetitive speech
Fragile X syndrome (FXS), the leading monogenic cause of intellectual disability and autism, is an X-linked disorder that has a complex pattern of inheritance. The behavioral symptoms that can be seen in the child with FXS are repetitive speech, poor eye contact, and hyperactivity. Delusions and hallucinations are seen in clients with schizophrenia, which is caused by an alteration in neurotransmitter levels. (B, D, E)
The primary health care provider prescribes BRCA1 and BRCA2 testing for a client with breast cancer. How does the nurse advise the client before preparing for the test? A. "Check your insurance coverage." B. "Avoid eating yogurt for few days." C. "Avoid wearing tight-fitting bras." D. "Bring your birth certificate with you."
Some insurance policies do not provide reimbursement for BRCA1 and BRCA2 tests. Therefore, the nurse should advise clients to check their insurance coverage before undergoing BRCA1 and BRCA2 testing. Consuming yogurt and wearing a tight-fitting bra will not alter the test results. Therefore, the nurse should not advise clients to avoid eating yogurt or not to wear tight-fitting bras. The BRCA1 and BRCA2 testing can be done for clients of any age group. Therefore, the nurse should not advise that clients bring their birth certificates. (A)
###The primary health care provider instructs the nurse to administer warfarin (Coumadin) to a child with venous thrombosis. What precaution should the nurse take to prevent possible severe adverse drug reactions in the child? Administer the genotype-guided dose of the drug. Administer the drug orally on an empty stomach. Administer a test dosage prior to the medication. Administer the drug by the intramuscular route.
Warfarin (Coumadin) is the drug of choice to treat children for thromboembolic events. However, for treatment to be effective and to prevent adverse effects, the dosage of warfarin (Coumadin) may have to be customized for each patient based on their genotype. This drug does not have to be given on an empty stomach. Warfarin (Coumadin) is not given as a test dose. Some antibiotics, but not warfarin (Coumadin), may be administered by testing a small dose first to determine hypersensitivity. This medication is not given by the intramuscular route. It is an anticoagulant and giving the medication through this route may cause bleeding. (A)
While caring for an infant with a genetic disorder, the nurse finds that the infant has a mewing cry, microcephaly, and unusual facial appearance. What does the nurse infer from this? A. The child has cri du chat syndrome. B. The child has velocardiofacial syndrome. C. The child has Turner syndrome. D. The child has Klinefelter syndrome.
Cri du chat syndrome is caused by deletion of the short arm of chromosome 5 and deletion of the long arm of chromosome 18. The children affected with this disorder typically have a mewing cry, severe mental retardation, microcephaly, and unusual facial appearance. Velocardiofacial syndrome is caused by microdeletion of the long arm of chromosome 22, and it is characterized by cardiac and craniofacial abnormalities. It is not characterized by a mewing cry. Turner syndrome is seen in females due to the absence of an X chromosome. It is characterized by webbing of the neck, a low hairline in the back, low-set ears, and lymphedema of the hands and feet. Klinefelter syndrome is seen in males and is due to the presence of an extra X chromosome. It is characterized by infertility and poor development of secondary sexual characteristics.
A female carries the gene for hemophilia on one of her X chromosomes. Her father does not have hemophilia. Now that she is pregnant she asks the nurse how this might affect her baby. The nurse should tell her: A. A female baby has a 50% chance of also being a carrier. B. A male baby can be a carrier or have hemophilia. C. Female babies are never affected by this disorder D. Hemophilia is always expressed if a male inherits the defective gene.
Key words: (Hemophilia carrier mom, Hemophilia, X chromosome, Father's impact?)(D)
Which factor is least likely to influence the decision to undergo genetic testing? A. Anxiety and altered family relationships B. Cost of testing or denial of insurance benefits C. Imperfection of test results D. Ethnic and socioeconomic disparity associated with genetic testing
Testing is not 100% accurate and has a high percentage of false-negative results. An individual may not take these results seriously and subsequently fail to have testing completed or to seek necessary follow-up consultation. Anxiety and altered family relationships are often the result of genetic testing. The results of genetic testing may be difficult to keep confidential, and family members may feel pressured to have testing performed. Decisions about genetic testing are shaped by socioeconomic status and the ability to pay for the testing. Some types of genetic testing are expensive and are not covered by insurance benefits. Caucasian middle-class families have greater access to genetic screening; therefore, this population is less at likely to decide against genetic testing. (B)
###The nursing instructor asks the students to submit a list of available genetic tests at the next class. To which online tool do the students refer to gather this information? Online Mendelian Inheritance in Man (OMIM) The Genetic Testing Registry Does It Run in the Family? My Family Health Portrait
The Genetic Testing Registry is an online tool that was launched by the National Institute of Health. It has a list of available genetic tests. OMIM is an online catalogue of human genes and disorders; it does not contain a list of genetic tests. Does It Run in the Family? and My Family Health Portrait are free online tools that help record one's family health history. These tools help identify whether family members are at risk of cardiovascular disorders, diabetes, and other related diseases. (B)
The nurse must be cognizant that an individual's genetic makeup is known as his or her? A. Genotype. B. Phenotype. C. Karyotype. D. Chromotype.
The genotype comprises all the genes the individual can pass on to a future generation. The phenotype is the observable expression of an individual's genotype. The karyotype is a pictorial analysis of the number, form, and size of an individual's chromosomes. Genotype refers to an individual's genetic makeup. (A)
What is the total count of chromosomes if the chorionic villus sampling report of a mother revealed the progeny to be in monosomic condition? A. 45 B. 54 C. 24 D. 42
Aneuploidic conditions are the most common cause of genetic disorders in humans that result in impaired cognitive levels. Monosomy is one such condition, in which the chromosome count is 45. In this condition the chromosome number is reduced due to the union of gametes. Therefore, the normal count of the chromosome is altered, and the result is 45 chromosomes. (A)
Which client requires genetic counseling during pregnancy? A. A client with iron deficiency B. A client with nausea and vomiting C. A client with neuromuscular disease D. A client with blood pressure 130/90 mm Hg
Clients with genetic disorders such as neuromuscular disease, cystic fibrosis, and factor V Leiden require specialized treatment during pregnancy. This helps promote proper fetal growth and development, and it also prevents complications during pregnancy. Iron deficiency causes anemia, which can be treated by prescribing iron supplements to the client. This does not require any specialized treatment. Nausea and vomiting are common symptoms observed during pregnancy. A blood pressure of 130/90 mm Hg indicates a slight increase in blood pressure. Adequate rest and a balanced diet will help reduce high blood pressure. (C)
On reviewing the genetic testing reports of a couple, the nurse finds that the male partner has color blindness. What does the nurse infer from this? A. The couple's male children would be carriers for color blindness. B. The couple's female children would be carriers for color blindness. C. The couple's male children would be affected by color blindness. D. The couple's female children would be affected by color blindness.
Color blindness is an X-linked recessive disorder. Females receive one X chromosome from the mother and another from the father. Therefore, an affected male would pass one X chromosome to the female child. Hence all the client's daughters would be carriers for color blindness. Males receive an X chromosome from the mother and a Y chromosome from the father. Because color blindness is an X-linked recessive disorder, the male children of the client would neither be carriers for nor be affected by color blindness. If the female partner is a carrier of color blindness and the male partner is affected with color blindness, then any female children of the couple will be affected by color blindness. (B)
A child born to a couple is diagnosed with cystic fibrosis. After reviewing the genetic reports, the couple is found to be carriers for the disorder. How should the nurse explain this to the couple? A. "This disorder is an X-linked recessive inherited disorder." B. "This disorder is an X-linked dominant inherited disorder." C. "The disorder is an autosomal recessive inherited disorder." D. "The disorder is an autosomal dominant inherited disorder."
Cystic fibrosis is an autosomal recessive disorder. It is inherited and expressed only when the individual carries both the genes for the abnormality. Because both parents are carriers, both of them contributed their recessive genes to the child. It is an autosomal recessive disorder and is not associated with X-linked recessive or dominant inheritance. Autosomal dominant disorders need only one copy of the gene for variation. If the gene for variation is carried on the dominant allele, the individual exhibits the disorder. (C)
The nurse is interacting with the parents of a newborn who is diagnosed with Down syndrome. What explanation should the nurse provide to the parents about the illness? A. "Down syndrome is caused by a decreased intake of folic acid." B. "Down syndrome is caused by an X-Liked recessive gene." C. "Down syndrome is caused by an autosomal recessive gene." D. "Down syndrome is caused by the presence of an extra chromosome."
Down syndrome is an intellectual disability caused by aneuploidy. Aneuploidy is a condition characterized by the presence or absence of an extra chromosome. Therefore, the presence of an extra chromosome 21 causes Down syndrome in the newborn. The deficiency of folic acid results in neural tube defects in the newborn. X-Liked recessive gene disorder is due to the presence of a defective gene on the X-chromosome of a carrier mother. Down syndrome is not caused by inheritance of an autosomal recessive gene. It occurs due to the extra chromosomal in an individual. (D)
The nurse is caring for a newborn with lymphedema of the limbs, webbing of the neck, and a low hairline in the back. What does the nurse infer from this? A. The child has a deficiency of a sex-linked chromosome. B. The child has a deficiency of an autosomal chromosome. C. The child has the presence of an extra sex linked chromosome. D. The child has the presence of an extra autosomal chromosome.
Lymphedema of the limbs, webbing of the neck, and a low hairline in the back are the symptoms of Turner syndrome. It occurs due to nondisjunction during gametogenesis in either of the parents, resulting in monosomy X (45 X). In most cases, either a paternal X- or Y-linked chromosome is lost. The deficiency of an autosomal chromosome results in Down syndrome, which is not characterized by the symptoms identified in the child. The presence of an extra sex-linked chromosome is seen in Klinefelter syndrome, which is characterized by poorly developed secondary sexual characteristics. The presence of an extra autosomal chromosome is also observed in Down syndrome, which is characterized by intellectual disability. (A)
With regard to prenatal genetic testing, nurses should be aware that: A. Maternal serum screening can determine whether a pregnant woman is at risk of carrying a fetus with Down syndrome. B. Carrier screening tests look for gene mutations of people already showing symptoms of a disease. C. Predisposition testing predicts with near certainty that symptoms will appear. D. Presymptomatic testing is used to predict the likelihood of breast cancer.
Maternal serum screening identifies the risk for the neural tube defect and the specific chromosome abnormality involved in Down syndrome. Carriers of some diseases such as sickle cell disease do not display symptoms. Predisposition testing determines susceptibility such as for breast cancer; presymptomatic testing indicates that, if the gene is present, symptoms are certain to appear. (A)
The nurse is providing genetic counseling for a patient with Stickler syndrome. What questions should the nurse ask the patient? A. "Was your father over 50 years old when you were born?" B. "Was your mother over 35 years old when you were born?" C. "May I ask what is the socioeconomic status of your family?" D. "Have you ever had any other children with birth defects?"
Stickler syndrome is an autosomal dominant disease caused by a mutation on a normal gene of an individual. Because the syndrome shows few symptoms, the nurse should assess the family history of the client. The nurse should also ask about whether or not the client has other children and if they have any birth defects due to the syndrome. The age of the parent plays a vital role in the diagnosis of Down syndrome. Therefore, it is not as important to know about the age of the client's mother and father. Socioeconomic status is not a cause of genetic abnormalities, so the nurse should not include the question about the socioeconomic status of the client during counseling. (D)
A father and mother are carriers of phenylketonuria (PKU). Their 2-year-old daughter has PKU. The couple tells the nurse that they are planning to have a second baby. Because their daughter has PKU, they are sure that their next baby won't be affected. What response by the nurse is most accurate? A. "Good planning; you need to take advantage of the odds in your favor." B. "I think you'd better check with your doctor first." C. "You are both carriers, so each baby has a 25% chance of being affected." D. "The ultrasound indicates a boy, and boys are not affected by PKU."
The chance is one in four that each child produced by this couple will be affected by PKU disorder. This couple still has an increased likelihood of having a child with PKU. Having one child already with PKU does not guarantee that they will not have another. These parents need to discuss their options with their physician. However, an opportune time has presented itself for the couple to receive correct teaching about inherited genetic risks. No correlation exists between gender and inheritance of the disorder, because PKU is an autosomal recessive disorder. (C)
A 32-year-old woman is pregnant for the third time. One child was born with cystic fibrosis, and the other child is healthy. The man wonders what the chance is that this child will have cystic fibrosis. This type of testing is known as: A. Occurrence risk. B. Recurrence risk. C. Predictive testing. D. Predisposition testing.
The couple already has a child with a genetic disease; therefore they will be given a recurrence risk test. If a couple has not yet had children but are known to be at risk for having children with a genetic disease, they are given an occurrence risk test. This couple already has a child with a genetic disorder. Predictive testing is used to clarify the genetic status of an asymptomatic family member. Predisposition testing differs from presymptomatic testing in that a positive result does not indicate 100% risk of a condition developing. (B)
While interacting with a couple, the nurse learns that they are planning to conceive. Which action would be most beneficial in preventing genetic disorders in the newborn? A. Collecting the medical history of the couple and their parents B. Collecting the family history of the couple during the preconception period C. Advising the couple to seek genetic testing during the second trimester D. Advising the couple to take a semen analysis test immediately
The nurse should collect the couple's family history during the preconception period. This will help provide appropriate treatment to reduce the risk of genetic disorders in the newborn. While collecting the family history, the nurse should also obtain the data of three generations to find if the newborn would act as a carrier or be affected by a genetic disorder, so a medical history of the couple and their parents would be incomplete. The nurse should also suggest that the couple undergo genetic testing during the preconception period. Taking the test during the second trimester may not be helpful, because the genetic information would already have been transferred to the fetus. A semen analysis test helps identify fertility in the male partner; it does not help diagnose whether the patient has genetic disorders. (B)
A client's prenatal screening test indicates that the fetus is at risk for Down syndrome. The client appears depressed and tells the nurse, "I'm not sure what to do; are there any tests or treatments that can help me?" A. "It sounds like you need more complete information. Let's discuss the diagnostic testing that is available." B. "You should consider whether to bring this pregnancy to term given the risks involved." C. "Screening results obtained are generally accurate, so further testing would be of little benefit." D. "Eating a protein-rich diet and taking folate supplements reduces the risk of Down syndrome."
The screening test is not 100% accurate, and further diagnostic testing is required for confirmation. The nurse should not advise against additional testing. Nurses should recognize their own values and attitudes related to genetics and not allow those attitudes to affect client care. Therefore, the nurse should not suggest that the client terminate the pregnancy. Genetic disorders cannot be treated by diet modification. Therefore, the nurse should not inform the client that eating a protein-rich diet and taking folate supplements will reduce the risk of Down syndrome. (A)
A woman who is gravida 2 and 16 weeks of gestation comes in for her prenatal appointment. Her 2-year-old daughter is with her and is wearing a sleeveless top. While interacting with her daughter, you note axillary freckling and several café-au-lait spots (>2 cm). In reviewing her chart, you would assess for documentation of which genetic disease? a. Tay-Sachs disease b. Galactosemia c. Neurofibromatosis (NF) d. Phenylketonuria
Clinical manifestations of NF may include axillary freckling and café-au-lait spots. Tay-Sachs disease is an incurable lipid-storage disorder and is not associated with café-au-lait spots. Galactosemia is an inborn error of metabolism and is also not associated with café-au-lait spots. PKU is not associated with café-au-lait spots. A child with PKU would have difficulty manufacturing the liver enzyme phenylalanine.
###The prenatal screening test indicates that the client's fetus has a risk of Down syndrome. Which characteristic feature would the nurse find in the in a child with Down syndrome after birth? Hyperflexibility Long and narrow hands Increased muscle tone Narrow space between large and second toes
Down syndrome is characterized by hyperflexibilty, increased flexibility in the joints and ligaments. Therefore, the nurse would find that a child with Down syndrome has hyperflexibilty. Down syndrome is characterized by growth retardation, due to which the child will have short and broad hands rather than long and narrow hands. Down syndrome is characterized by muscle weakness, so the child would have decreased muscle tone rather than increased muscle tone. Children with Down syndrome typically have a large gap between their large and second toes. (A)
The nurse examines the genetic report of a client with Down syndrome. What chromosome count does the nurse expect in the client's report? A. All the cells contain 45 chromosomes. B. All the cells contain 46 chromosomes. C. Most of the cells contain 47 chromosomes. D. Most of the cells contain 45 chromosomes.
Down syndrome is the most common trisomal abnormality. Trisomy is the fusion of a normal gamete with a gamete containing an extra chromosome. Therefore, the client with Down syndrome may have 47 chromosomes in most cells. A client with monosomy may have 45 chromosomes. Monosomy does not lead to Down syndrome. A person with 46 chromosomes might be a healthy person. (C)
Which statement most accurately describes dominant genetic disorders? A. With a dominant disorder, the likelihood of the second child also having the condition is 100%. B. An autosomal recessive disease carries a one-in-eight risk of the second child also having the disorder. C. Disorders involving maternal ingestion of drugs carry a one-in-four chance of being repeated in the second child. D. The risk factor remains the same no matter how many affected children are already in the family.
Each pregnancy is an independent event. The risk factor (e.g., one-in-two, one-in-four) remains the same for each child, no matter how many children are born to the family. In a dominant disorder, the likelihood of recurrence in subsequent children is 50% (i.e., one-in-two). An autosomal recessive disease carries a one-in-four chance of recurrence. In disorders involving maternal ingestion of drugs, subsequent children would be at risk only if the mother continued to take the drugs; the rate of risk would be difficult to calculate. (D)
An 18-year-old patient has hearing impairment associated with facial pain, headaches, and facial numbness. The nurse observes that the patient is unable to stand properly. What does the nurse infer from these symptoms?? A. The client may have a deficiency of liver enzymes. B. The client may have deficiency of merlin protein. C. The client may have the factor V Leiden (FVL) mutation. D. The client may be missing an X chromosome.
Facial pain, headaches, and facial numbness are symptoms associated with neurofibromatosis 2 (NF2). It is also associated with poor balance and hearing loss in teenagers. It is due to a defect in chromosome 22, which is involved in the production of merlin, a protein that suppresses tumor formation. These tumors often cause pressure damage to nearby nerves and result in headaches, facial pain, and facial numbness. Deficiency of liver enzymes is associated with phenylketonuria. It is not associated with facial pain, headache, or facial numbness. The Factor V Leiden (FVL) mutation results in embedded blood clots in the lungs and the large blood vessels of legs. Missing an X chromosome results in Turner syndrome, and the client would have underdeveloped ovaries. It is not related to neurofibromatosis. (B)
Which of the following statements are true with regard to Factor V Leiden? (Select all that apply.) A. Factor V Leiden is an autosomal dominant disorder. B. It increases the likelihood of DVT in an affected patient. C. It is due to a mutation in factor IV and V genes. D. A woman who has one copy of the gene should not use oral contraceptives as a birth control method. E. Factor V Leiden leads to increased susceptibility of activated protein C.
Factor V Leiden is an inherited disorder via autosomal dominant transmission. Presence of this genetic mutation increases the likelihood for blood clots to develop. This genetic mutation is found in Factor V gene only. A patient who tests positive for Factor V Leiden, regardless of whether she is homozygous or heterozygous for the trait, should not use oral contraceptives as a birth control method. The Factor V Leiden mutation leads to activated protein C resistance.(A,B,D)
###The genetic screening of a newborn is indicative of phenylketonuria. The nurse learns that the couple has no history of genetic disorders in the past three generations. What other tests does the nurse suggest to the couple to determine the reason for the genetic disorder? A. Sonography of the fetus B. Genetic testing of the couple C. Chorionic villus sampling D. Maternal serum screening
Genetic testing of the couple may determine if the parents of the newborn are carriers for the mutation. Phenylketonuria can be seen in the newborn only if both parents are carriers for the disorder. Fetal sonography is a technique of imaging the fetus in the uterus using high-frequency sound waves. Chorionic villus sampling is a prenatal diagnostic technique to determine chromosomal disorders in the fetus. Maternal serum sampling is carried out on the mother through a blood test to screen for a high risk of carrying a fetus with neural tube defects or genetic abnormalities. (B)
With regard to the estimation and interpretation of the recurrence of risks for genetic disorders, nurses should be aware that: A. With a dominant disorder, the likelihood of the second child also having the condition is 100%. B. An autosomal recessive disease carries a one in eight risk that the second child will also have the disorder. C. Disorders involving maternal ingestion of drugs carry a one in four chance of being repeated in the second child. D. The risk factor remains the same no matter how many affected children are already in the family.
In a dominant disorder, the likelihood of recurrence in subsequent children is 50% (one in two). An autosomal recessive disease carries a one in four chance of recurrence. Subsequent children of a mother who used drugs would be at risk only if she continued to do so; the rate of risk would be difficult to calculate. Each pregnancy is an independent event. The risk factor (e.g., one in two, one in four) remains the same for each child, no matter how many children are born to the family. (D)
While caring for a client with a myocardial infarction, the nurse finds that the primary health care provider has prescribed a lower initial dose of warfarin (Coumadin). What is the reason for this? A. The client is Caucasian. B. The client has variation in the CYP2C9 gene. C. The client has variation in the HER2/neu gene. D. The client has a family history of myocardial infarction.
In order to reduce the adverse effects of the medication in clients, the dose of the drug should be adjusted according to the genetic mutations found in various clients. Warfarin (Coumadin) is not completely metabolized in client with variation in the CYP2C9 gene. Therefore, to prevent toxic effects of warfarin (Coumadin), an initial low dose should be prescribed to clients with a variation in the CYP2C9 gene. Unlike monoclonal antibodies, warfarin (Coumadin) does not target the HER2/neu gene due to variation in the structure. Therefore, variation in the HER2/neu gene does not require prescribing a low dose of warfarin (Coumadin). Warfarin (Coumadin) metabolism is not impaired in Caucasians or in clientswith a family history of myocardial infarction. Therefore, it is not recommended to prescribe an initial low dose of warfarin (Coumadin) to these clients. (B)
Cancer is genetic and begins with one or more genetic mutations. A cancer specifically being investigated in this regard is: a. Lung cancer b. Liver cancer c. Colorectal cancer d. Oral cancer
Incorrect: These types of cancers are the result of mutated oncogenes. Incorrect: These types of cancers are the result of mutated oncogenes. Correct: Colorectal cancer usually results from one or more predisposing genes. Incorrect: These types of cancers are the result of mutated oncogenes.
A pregnant woman carries a single gene for cystic fibroses, an inborn error of metabolism. The father of her baby does not carry this gene. Which of the following is true regarding the genetic pattern of the inborn error of metabolism as it applies to this family? A. The pregnant woman has cystic fibrosis B. There is a 50% chance her baby will have the disorder. C. There is a 25% chance her baby will be a carrier. D. There is no chance her baby will be affected by this disorder.
Key words: (Carriers, inborn error of metabolism, Recessive or dominant?, cystic fibrosis) (D)
Based on genetic testing of a newborn, a diagnosis of neurofibromatosis is made. The parents ask the nurse if this could happen to future children. Because this is an example of autosomal dominant inheritance, the nurse tells the parents: A. " For each pregnancy, there is a 50/50 chance the child will be affected by neurofibromatosis" B . "This will not happen again because the neurofibromatosis was cased by the harmful genetic effects of the infection you had during pregnancy." C. "For each pregnancy there is a 25% chance the child will be a carrier of the defective gene but unaffected by the disorder." D. "Because you already have had an affected child, there is a decreased chance of this happening in future pregnancies."
Key words: (Neurofibromatosis, Future Children, Autosomal dominant inheritance) (A)
A nurse is assessing the knowledge of new parents of a child born with Klinefelter syndrome. Which statement accurately describes this genetic disorder? A. Klinefelter syndrome is a sex chromosome abnormality. B. It affects only female children. C. The disorder is expressed as trisomy XYY. D. The child with this disorder will grow to be infertile.
Klinefelter syndrome, also known as trisomy XXY, is a sex chromosomal deviation that is expressed in males. Turner syndrome (monosomy X) is displayed in females. Most males with Klinefelter syndrome are tall, may be infertile, and are slow to learn; however, those who have mosaic Klinefelter syndrome may be fertile as adults. (A)
The nurse is assessing the knowledge of new parents with a child born with maple syrup urine disease (MSUD). This is an autosomal recessive inherited disorder, which means that A. Both genes of a pair must be abnormal for the disorder to be expressed. B. Only one copy of the abnormal gene is required for the disorder to be expressed. C. The disorder occurs in males and heterozygous females. D. The disorder is carried on the X chromosome.
MSUD is a type of autosomal recessive inheritance disorder in which both genes of a pair must be abnormal for the disorder to be expressed. MSUD is not an X-linked dominant or recessive disorder or an autosomal dominant inheritance disorder. (A)
After reviewing the maternal serum screening results of a pregnant patient, the nurse infers that the patient may be carrying a child with Down syndrome. What is the potential finding in the report? A. Trisomy B. Triploid C. Tetralogy E. Tetraploidy
Maternal serum screening is the diagnostic tool used for detecting chromosomal abnormalities in the fetus. It helps to detect whether the fetus has an increased risk of Down syndrome or neural tube defects. The condition in which an extra chromosome exists is called trisomy. Trisomy is an aneuploidic condition in with the chromosome count is 47 (XXX). The incidence of Down syndrome is high in a child with trisomy. The chromosome count for a female child with a triploid condition is 69 (3N). The chromosome count for a female child with tetrasomy is 48 (XXXX). The chromosome count for a female child with tetraploidy is 92 (4N). The incidence of Down syndrome is not high in these conditions (A)
The primary health care provider recommends genetic screening to a pregnant client to identify the risk of Down syndrome in the fetus. The client requests a noninvasive test. Which test does the nurse expect that the provider will order for the client? A. Amniocentesis B. Urine analysis C. Maternal serum testing D. Chronic villus sampling
Maternal serum testing is a blood test that is used to identify whether the fetus of a pregnant client is at risk for Down syndrome. It is a noninvasive technique that requires only the maternal serum sample. Amniocentesis is an invasive technique that is used for testing fetal aneuploidy. Urine analysis is involved in the detection of pregnancy, but is not used to detect chromosomal abnormalities. Chronic villus sampling is also an invasive technique that is used for determining fetal aneuploidy. (C)
Which findings can be observed in the individuals with mosaicism on an autosomal gene? A. Neural tube defect B. Down syndrome C. Congenital heart defect D. Normal intelligence
Mosaicism is a condition in which the individual may have an extra chromosome in some of the cells. This disorder is usually associated with sex chromosomes. It is found to be present on an autosomal gene and results in Down syndrome in the majority of individuals. Neural tube defects are due to the deficiency of folic acid during pregnancy. Congenital heart defect is a multifactorial inheritance caused due to environmental and chromosomal defects. The child will not be born with normal intelligence. (B)
Most of the genetic tests now offered in clinical practice are tests for? A. Single-gene disorders. B. Carrier screening. C. Predictive values. D. Predispositional testing.
Most tests now offered are tests for single-gene disorders in clients who have clinical symptoms or a family history of a genetic disease. Carrier screening is used to identify individuals who have a gene mutation for a genetic condition but do not display symptoms. Predictive testing is used only to clarify the genetic status of asymptomatic family members. Predispositional testing differs from the other types of genetic screening in that a positive result does not indicate a 100% chance that the condition will develop. (A)
Which type of genetic tests in clinical practice are most often offered to clients with a family history of disease? a. Single-gene disorders b. Carrier screening c. Predictive value testing d. Predispositional testing
Most tests now offered are tests for single-gene disorders in clients with clinical symptoms or clients who have a family history of a genetic disease. Carrier screening is used to identify individuals who have a gene mutation for a genetic condition but do not display symptoms. Predictive value testing is used only to clarify the genetic status of asymptomatic family members. Predispositional testing differs from the other types of genetic screening in that a positive result does not indicate a 100% chance of developing the condition. (A)
A pregnant client tells the nurse, "I want to know whether or not my family history indicates any risk for genetic disorders in my child." Which cost-effective method does the nurse suggest to the client? A. My Family Health Portrait B. The Genetic Testing Registry C. Genetic testing D. Gene therapy
My Family Health Portrait is an online tool that is used for organizing the client's medical history. It is a cost-effective method and helps find whether the fetus is at risk of any possible genetic defects. The medical history of both parents is assessed, and a final conclusion is made about possible genetic defects in the fetus. Although My Family Health Portrait detects only the genetic defects that are hereditary, it is primarily used to assess genetic disorders during maternity. The Genetic Testing Registry contains all the possible genetic tests available for various disorders. Genetic testing detects defects in the fetus, but it bears more cost than My Family Health Portrait. Gene therapy is involved in treating genetic disorders but is not involved in the detection of genetic disorders. (A)
In practical terms regarding genetic health care, nurses should be aware that: A. Genetic disorders affect equally people of all socioeconomic backgrounds, races, and ethnic groups. B. Genetic health care is more concerned with populations than individuals. C. The most important of all nursing functions is providing emotional support to the family during counseling. D. Taking genetic histories is the province of large universities and medical centers.
Nurses should be prepared to help with a variety of stress reactions from a couple facing the possibility of a genetic disorder. Although anyone may have a genetic disorder, certain disorders appear more often in certain ethnic and racial groups. Genetic health care is highly individualized because treatments are based on the phenotypic responses of the individual. Individual nurses at any facility can take a genetic history, although larger facilities may have better support services. (C)
The nurse is working in an obstetric ward. What does the nurse do to reduce the risk of genetic disorders in newborns? Select all that apply. A. Refer the client to genomic services when required. B. Develop a care plan that incorporates genomic assessment. C. Assess the client's knowledge regarding genetic disorders. D. Suggest that clients with congenital anomalies avoid pregnancy. E. Suggest maternal serum testing to clients with multiple gestations.
Nurses who care for pregnant clients and newborns should take measures to prevent genetic abnormalities in the newborns, including a care plan that incorporates genetic assessment. This helps determine whether the client's fetus is at risk of genetic disorders. The nurse should assess the client's knowledge regarding genetic disorders and provide accurate information and counseling. The nurse should refer clients with a history of a sickle cell anemia, cystic fibrosis, or other genetic disorders to specific genomic services. The American College of Obstetricians and Gynecologists (ACOG) has determined that the maternal serum test, which is a noninvasive method of screening, may not be accurate in clients with multiple gestations. In this situation, suggesting that the client avoid pregnancy is unprofessional behavior. (A,B,C)
During the assessment of a 19-year-old client, the nurse finds that the client is worried. The client reports an inability to grow a moustache or a beard. The laboratory results indicate that the client has an extra X chromosome. What would be the nurse's best response? A. "I advise visiting a genetic counselor for follow-up." B. "You may not develop a mustache, but you are fertile." C. "I will get you a prescription to begin taking oral steroids." D. "You will develop a beard and mustache after some time."
Poorly developed secondary sexual characteristics such as facial hair in men and the presence of small testes are the hallmark features of Klinefelter syndrome. It occurs due to the presence of an extra X chromosome. The nurse should instruct the client to have genetic counseling to prevent other complications associated with these disorders. The client with Klinefelter syndrome is usually infertile, tall, and effeminate. Therefore, the nurse should not give false information that the client is fertile. Steroids are prescribed for muscle growth. They do not help in the development of secondary sexual characteristics. The nurse should not give false assurance by saying that a beard and mustache will develop after some time, because this may cause mistrust in the client. (A)
A new father has just been told that his child has trisomy 18. Which identifying physical feature is unique to an infant with this genetic disorder? A. Microcephaly and capillary hemangiomas B. Epicanthal folds and a simian crease C. Oblique palpebral fissures and cri du chat syndrome D. Rocker-bottom feet and clenched hands with overlapping fingers
Rocker-bottom feet and clenched hands with overlapping fingers are associated with trisomy 18. Microcephaly and capillary hemangiomas are associated with trisomy 13. Epicanthal folds and a simian crease are associated with trisomy 21 (Down syndrome). Deletion of the short arm of chromosome number 5 is manifested by Cri du chat syndrome. (D)
###On reviewing the genetic reports of a 1-month-old infant, the nurse finds that the infant has Tay-Sachs disease. What clinical findings and symptoms does the nurse find in the child? Select all that apply. A. The child has beautiful facial features. B. The child has a deficiency of phenylalanine hydroxylase. C. The child has a deficiency of hexosaminidase. D. The child has cleft palate and rocker-bottom feet. E. The child has cardiac abnormalities
Tay-Sachs disease is an autosomal recessive genetic disorder. Infants affected with Tay-Sachs disease appear to be normal until 6 months of age and have very beautiful facial features. This disease is caused by a deficiency of hexosaminidase, which results in neurodegenerative disorders. A deficiency of phenylalanine hydroxylase causes phenylketonuria. Therefore, the nurse would not find a deficiency of phenylalanine hydroxylase in the infant with Tay-Sachs disease. Cleft palate and rocker-bottom feet are characteristic features of Edward syndrome. Cardiac abnormalities are observed in children with velocardiofacial syndrome, Down syndrome, Edward syndrome, and Patau syndrome. The nurse would not expect to find cleft palate, rocker-bottom feet, or cardiac abnormalities in a child with Tay-Sachs disease. (A,C)
The primary health care provider has ordered cell free fetal DNA (cffDNA) testing, a noninvasive prenatal test, for a pregnant client. The nurse alerts the primary care provider that this particular client is not a candidate for this specific test. What is the possible reason? A. The client's first child has trisomy 18. B. The client has gestational diabetes. C. The client has multiple gestations. D. The client is 35 years old.
The American College of Obstetricians and Gynecologists (ACOG) has determined that the prenatal screening test for aneuploidy is safe and effective in all clients. However, it does not recommend noninvasive prenatal testing to clients with multiple gestations. The effectiveness of noninvasive prenatal screening in the present pregnancy is not affected by the genetic abnormalities of the previous child. Therefore, noninvasive prenatal testing is recommended to the client whose first child has trisomy 18. The test is safe and effective for all age groups, and the results do not change even if the client is 35 years old. An increase in blood glucose levels does not alter the test results, so the noninvasive test is effective for clients with gestational diabetes. (C)
On reviewing the genetic reports of three children X, Y, and Z, the nurse finds that X has mosaic Down syndrome, Y has trisomy 18, and Z has trisomy 13. What does the nurse observe while caring for these children? A. X is more intelligent than Z. B. Y has a longer life span than X. C. Y has more abnormalities than Z. D. Y and Z do not have visual abnormalities.
The child with mosaic Down syndrome (X) has more intelligence when compared to the children with trisomy 18 (Y) or trisomy 13 (Z). Trisomy 18 and trisomy 13 are characterized by severe intellectual disability. Therefore, X would be more intelligent than Y. The children with trisomy 18 or trisomy 13 would have shorter life spans when compared to the child with mosaic Down syndrome. Therefore, X would have a longer life span than Y. Children with trisomy 13 have numerous abnormalities such as renal and genital disorders, cleft palate, and so on. Therefore, Z has more abnormalities than Y. Children with trisomy 13 have visual abnormalities and central nervous abnormalities. Therefore, the child with trisomy 13 (Z) may have visual abnormalities. (A)
***A nurse is providing genetic counseling for an expectant couple who already have a child with trisomy 18. The nurse should: A. Tell the couple they need to have an abortion within 2 to 3 weeks. B. Explain that the fetus has a 50% chance of having the disorder. C. Discuss options with the couple, including amniocentesis to determine whether the fetus is affected. D. Refer the couple to a psychologist for emotional support.
The couple should be given information about the likelihood of having another baby with this disorder so that they can make an informed decision. A genetic counselor is the best source for determining genetic probability ratios. Genetic testing, including amniocentesis, would need to be performed to determine whether the fetus is affected. The couple eventually may need emotional support, but the status of the pregnancy must be determined first. (c)
The nurse is assessing a client who has been prescribed anticoagulant medications. Upon reviewing the genetic test reports, the nurse finds that the client has the factor V Leiden mutation. What does the nurse suggest the client do to reduce the risk of deep venous thrombosis and pulmonary embolism? A. Avoid taking anticoagulants. B. Avoid eating protein-rich food. C. Avoid taking oral contraceptives. D. Avoid eating food rich in vitamin C.
The factor V Leiden mutation causes thrombophilia and abnormal clotting of the blood, and increases the risk of deep venous thrombosis and pulmonary embolism. Oral contraceptives reduce the efficiency of activated protein C and increase the risk of deep venous thrombosis and pulmonary embolism. Therefore, the nurse should suggest that the client avoid taking oral contraceptives. Anticoagulants are prescribed to clients, because they prevent clotting and reduce the risk of deep venous thrombosis. Protein and vitamin C will not affect the clotting process and do not increase the risk of deep venous thrombosis or pulmonary embolism. Therefore, the nurse should not suggest that the client avoid consuming food rich in protein or vitamin C. (C)
Which statement describes a key finding of the Human Genome Project? A. Humans produce one protein per gene. C. All human beings are 99.9% identical at the deoxyribonucleic acid (DNA) level. C. The Human Genome Project has not yet been able to translate the accumulating raw research into anything medically practical. D. Humans have more genes than other species.
The majority of the 0.1% genetic variations are found within and not among populations. Most human genes produce at least three proteins. The project's research has been very valuable in the identification of genes involved in disease and in the development of genetic testing. There are 20,500 genes in the human genome; scientists originally estimated more than 50,000 genes. Human genes are more efficient than the genes in other species, thereby increasing the human genetic complexity. (B)
***A newborn is diagnosed with Klinefelter syndrome. On assessing the family, the nurse finds that the couple feel embarrassed by the child. How should the nurse help the couple in coping up with the situation? Select all that apply A. Suggest giving up the child for adoption. B. Explain the main reason for the disorder. C. Direct the family to a genetic counselor. D. Educate the family about the disorder. E. Instruct about places to leave the child.
The nurse explains the cause of the disorder to the couple and their family members. The disorder is caused by a nondisjunction of sex chromosomes and the child is not responsible for it. Genetic counseling for the family may provide detailed knowledge of the syndrome and the possibility of future children having the syndrome. This may help the family to more effectively understand the disorder. Understanding the symptoms and treatment methods would help the parents and the family members to adjust according to the needs of the child. The nurse should motivate the family to accept the child, and not give the child up for adoption or find places to leave the child. The nurse also explains the emotional support that the child requires in the coming years and that it is the right of the child to be with parents. (B,C,D)
The nurse is assessing a 40-year-old client who is 12 weeks pregnant. What should the nurse anticipate based on the client's age? A. The fetus is at a risk of Down syndrome. B. The client is at a risk of sickle cell anemia. C. The fetus is at a risk of neural tube defects. D. The client is at a risk of Huntington's disease (HD).
The risk of Down syndrome increases in the fetus as the age of the pregnant mother increases. Because the patient is older than 35 years of age, the fetus is at an increased risk of having Down syndrome. The development of sickle cell anemia is not related to the age of the mother. It is caused due to inheritance of the defective genes from the parents. Neural tube defects in the fetus are sometimes due to insufficient intake of folic acid during pregnancy. HD is an autosomal-dominant disorder caused by a mutation on the normal gene and is not related to the age of the patient. (A)
A client's prenatal screening test indicates that the fetus is at risk for Down syndrome. The client appears depressed and tells the nurse, "I'm not sure what to do; are there any tests or treatments that can help me?" How does the nurse respond to the client? A. "It sounds like you need more complete information. Let's discuss the diagnostic testing that is available." B. "You should consider whether to bring this pregnancy to term given the risks involved." C. "Screening results obtained are generally accurate, so further testing would be of little benefit." D. "Eating a protein-rich diet and taking folate supplements reduces the risk of Down syndrome."
The screening test is not 100% accurate, and further diagnostic testing is required for confirmation. The nurse should not advise against additional testing. Nurses should recognize their own values and attitudes related to genetics and not allow those attitudes to affect client care. Therefore, the nurse should not suggest that the client terminate the pregnancy. Genetic disorders cannot be treated by diet modification. Therefore, the nurse should not inform the client that eating a protein-rich diet and taking folate supplements will reduce the risk of Down syndrome. (A)
###The nurse is assessing a 19-year-old female client who has webbed neck, underdeveloped ovaries, and edematous hands and legs. What other information does the nurse find in order to conclude that the client has a sex chromosome abnormality? Select all that apply. A. The client has an extra X chromosome. B. The client has small external genitalia. C. The client has a low intelligence quotient. D. The client has a low hairline in the back. E. The client has an extra Y chromosome.
Webbed neck, underdeveloped ovaries, and swelling of the hands and legs are symptoms of Turner syndrome. Turner syndrome is observed in females and is characterized by small external genitalia and underdeveloped ovaries. These clients may also have low intelligence quotients. They have a low hairline in the back and low-set ears. An extra X chromosome is present in male clients with Klinefelter syndrome. An extra Y chromosome is observed in male clients with XYY syndrome. Neither of these is a feature of Turner's syndrome. (B,C,D)
A maternal-newborn nurse caring for a mother who just delivered a baby born with Down syndrome. What nursing diagnosis would be the most essential in caring for the mother of this infant? A. Disturbed body image B. Interrupted family processes C. Anxiety D. Risk for injury
Women commonly experience body image disturbances in the postpartum period, but this development is unrelated to giving birth to a child with Down syndrome. This mother likely will experience a disruption in the family process related to the birth of a baby with an inherited disorder. She likely will also have a mix of emotions that may include anxiety, guilt, and denial, but anxiety is not the most essential nursing diagnosis for this family. Risk for injury is not an applicable nursing diagnosis. (B)
